What Is the Difference between “Safety” and “Liveness” in a Consensus Protocol?
Safety ensures that all honest nodes agree on the same sequence of transactions and that committed transactions are final and will never be reversed. It means "nothing bad happens." Liveness ensures that the system continues to process new transactions and that honest nodes will eventually agree on a new block.
It means "something good eventually happens." Both are critical properties, but some protocols may prioritize one over the other under specific failure conditions.
Glossar
Safety
Resilience ⎊ This encompasses the system's ability to withstand malicious attacks or unexpected hardware failures without losing committed transactions or exposing user funds, a non-negotiable prerequisite for handling cryptocurrency and derivatives.
Consensus Protocol
Protocol ⎊ Consensus Protocol is the set of deterministic rules and economic incentives that enable a distributed network of independent nodes to agree on a single, valid history of transactions without reliance on a central authority.
Liveness
Verification ⎊ Liveness, within cryptocurrency and financial derivatives, denotes the continuous confirmation of system state and operational integrity, crucial for maintaining trust and preventing manipulation.